Restore Your Truck’s Brain and Get Back to Work
Is your 2013-2014 GM HD truck or van suddenly refusing to start, running rough, or throwing a cascade of confusing check engine lights? The Engine Control Module (ECM) is the central command center for your 6.6L Duramax engine. When it fails, it can cause system-wide chaos, leaving your workhorse stranded. This isn’t just an inconvenience; it’s lost time and money. This listing is for a reliable, tested OEM ECM (service no. 12653319 or 12654088) that gets you back on the road without the dealership price tag.
We take the guesswork and hassle out of the replacement process. Before we ship this module, our technicians will program it with the latest official GM software, calibrated specifically to your vehicle’s VIN. This ensures that when you receive the part, it’s ready for the final installation and security relearn steps, saving you a costly trip for initial programming.
Case Study: The No-Communication Nightmare
A 2014 Silverado 2500 was towed into my bay last month. The owner, a contractor, said it died at a job site and wouldn’t crank. His local mechanic had replaced the battery and checked fuses but was stumped. My scan tool couldn’t communicate with the ECM—a classic sign of total failure, often confirmed with a U0100 code. After confirming power and ground to the module were good, we identified a fried ECM. In my experience with these 6.6L Duramax trucks, this is often caused by voltage spikes from improper jump-starting or water intrusion from a damaged cowl seal. We replaced it with a VIN-programmed module just like this one, performed the security relearn, and the truck fired right up, getting the owner back to his business the next day.
Is Your GM Truck or Van Showing These Symptoms?
- ✔ Complete no-start or crank-no-start condition.
- ✔ Check Engine Light is on with communication error codes (e.g., U0100, U0101).
- ✔ Specific internal processor fault codes like P0601 or P0606.
- ✔ Poor engine performance, misfires, or drastically reduced fuel economy.
- ✔ Erratic automatic transmission shifting or failure to shift.
- ✔ Problems with fuel injectors or other engine sensors that test fine individually.
- ✔ The cooling fans run constantly, even when the engine is cold.
Your Straightforward Installation Guide
Replacing the ECM is a manageable job for a DIYer or any professional technician. The critical part is the electronic relearn procedure after the physical swap. Follow these steps for the physical installation.
- Safety First: Always disconnect the negative battery terminal and wait at least 15 minutes for the vehicle’s capacitors to discharge.
- Locate the ECM: On Express and Savana vans, it’s in the left-hand rear of the engine compartment. On Sierra and Silverado pickups, it’s on the left-hand front side of the engine compartment.
- Disconnect Connectors: Carefully release the locking tabs on the main wiring harness connectors and pull them straight out. Never force them. Inspect the pins for any corrosion or damage.
- Remove the Module: Unbolt the ECM from its mounting bracket. Keep the hardware safe for reinstallation.
- Install the New ECM: Mount your VIN-programmed replacement ECM securely onto the bracket.
- Reconnect Everything: Firmly plug the wiring harnesses back in until they click, and re-engage the locking tabs. Reconnect the negative battery terminal.
- Perform Relearn Procedures: The vehicle will NOT start until a Vehicle Theft Deterrent (VTD) relearn is completed using a capable scan tool or GM’s TIS2Web service. Other procedures, like a crankshaft position variation relearn, may also be necessary for optimal performance.
Guaranteed Fitment for Your GM HD Vehicle
This module is a direct-fit replacement for the following vehicles equipped with the 6.6L diesel engine. Please verify your service number (serv.no) on your original part matches 12653319 or 12654088.
- 2013-2014 Chevrolet Silverado 2500 / 3500
- 2013-2014 GMC Sierra 2500 / 3500 (including Denali)
- 2013-2014 Chevrolet Express 2500 / 3500 Van
- 2013-2014 GMC Savana 2500 / 3500 Van
Note for Van Models: Fits models without the ‘pull-ahead design’ for 2014.
Frequently Asked Questions
Frequently Asked Questions
Do I need to program this ECM?
No. We handle the initial programming for you. Simply provide your vehicle’s 17-digit VIN during checkout, and we will flash the module with the correct, updated GM software for your specific vehicle before shipping.